The route first became important as a mule track in the fifteenth century when the route between Thusis and Splügen was known as the Via Mala. A road for wheeled vehicles was opened in 1770; this road was significantly improved between 1821 and 1823, financed in part by the Kingdom of Sardinia, keen to improve a trade route connecting Genoa and Piedmont to the Graubünden that was not directly controlled by Austria.

Traffic flow was much facilitated when in 1967, the San Bernardino road tunnel was completed, since then vehicle traffic on the pass has been reduced, benefiting those taking the time to avoid the tunnel. The pass road is only open in summer.